Well, I tried this once before with Grover Cleveland, and it turned out he wasn't that hard. Now, I shall make it tough on you. Franklin Pierce was the single most unpopular man to ever hold the office. After his time in office was up, his OWN PARTY were making campaign signs reading "anyone but Pierce"! A real challenge now: make Franklin Pierce a serious contender for greatest President in US history. Bonus points if he's remembered fondly both by the public and by later historians.